/in/foo.c: In function 'main':
/in/foo.c:5:16: error: array size missing in 'a'
  int xmin,xmax,a[][2],num=0;
                ^
/in/foo.c:8:6: error: 'i' undeclared (first use in this function)
  for(i=0;i<num;i++)
      ^
/in/foo.c:8:6: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c:9:7: error: 'j' undeclared (first use in this function)
   for(j=0;j<2;j++)
       ^
/in/foo.c:11:3: error: expected ';' before 'printf'
   printf("\n");
   ^~~~~~
/in/foo.c: In function 'find':
/in/foo.c:16:10: warning: variable 'x' set but not used [-Wunused-but-set-variable]
  int i,j,x,num=0;
          ^
/in/foo.c:16:8: warning: unused variable 'j' [-Wunused-variable]
  int i,j,x,num=0;
        ^